[PATCH] UBUNTU: SAUCE: AppArmor: Fix change_onexec when called from a confined task

John Johansen john.johansen at canonical.com
Tue Mar 27 11:16:06 UTC 2012

Patch submitted upstream, but not merged yet.

Fix failure in aa_change_onexec api when the request is made from a confined
task.  This failure was caused by two problems

 The AA_MAY_ONEXEC perm was not being mapped correctly for this case.

 The executable name was being checked as second time instead of using the
 requested onexec profile name, which may not be the same as the exec
 profile name. This mistake can not be exploited to grant extra permission
 because of the above flaw where the ONEXEC permission was not being mapped
 so it will not be granted.

BugLink: http://bugs.launchpad.net/bugs/963756

Signed-off-by: John Johansen <john.johansen at canonical.com>
 security/apparmor/domain.c |    3 ++-
 security/apparmor/file.c   |    2 ++
 2 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
index 51cd053..afa8671 100644
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -415,7 +415,8 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm)
 		 * exec\0change_profile
 		state = aa_dfa_null_transition(profile->file.dfa, state);
-		cp = change_profile_perms(profile, cxt->onexec->ns, name,
+		cp = change_profile_perms(profile, cxt->onexec->ns,
+					  cxt->onexec->base.name,
 					  AA_MAY_ONEXEC, state);
 		if (!(cp.allow & AA_MAY_ONEXEC))
diff --git a/security/apparmor/file.c b/security/apparmor/file.c
index 3022c0f..5d176f2 100644
--- a/security/apparmor/file.c
+++ b/security/apparmor/file.c
@@ -215,6 +215,8 @@ static struct file_perms compute_perms(struct aa_dfa *dfa, unsigned int state,
 	/* change_profile wasn't determined by ownership in old mapping */
 	if (ACCEPT_TABLE(dfa)[state] & 0x80000000)
 		perms.allow |= AA_MAY_CHANGE_PROFILE;
+	if (ACCEPT_TABLE(dfa)[state] & 0x40000000)
+		perms.allow |= AA_MAY_ONEXEC;
 	return perms;

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